1. Field of the Invention
The present invention relates to an air conditioning system, and more particularly, to a combined ventilating and air conditioning system, capable of being operated as a dehumidifying device and ventilator in both an air cooling mode and an air heating mode.
2. Background of the Related Art
In general, an air conditioner set conditions on the air within a specific area, by adjusting temperature, humidity, air motion, and cleanliness of the air.
For example, the air conditioner is similar to a heating and cooling system that cools or heats up the air in the interiors of a house, restaurant, library, or office.
FIG. 1 is a schematic diagram of a heating and cooling system of an air conditioner of the related art.
The construction and operational characteristics of the general heating and cooling system will be explained with reference to FIG. 1, followed by the problems with the system.
At first, the general hating and cooling system comprises a compressor 1, an refrigerant passage controller 2, an indoor heat exchanger 3, an outdoor heat exchanger 4, and an expansion device 5. In the vicinity of the outdoor heat exchanger 4, an outdoor blowing fan 4a is provided. Similarly, in the vicinity of the indoor heat exchanger 3, an indoor blowing fan 3a is provided.
The above heating and cooling system guides refrigerants emitted from the compressor 1 by the motion controller 2 selectively to the indoor heat exchanger 3 or the outdoor heat exchanger 4, according to the mode of system operation. Typically, the refrigerant passage controller 2 comprises a four-port valve.
Next, the operation of the heating and cooling system in an air cooling mode is explained.
The compressed refrigerant at a high temperature and a high pressure in the compressor is led to the outdoor heat exchanger via the four-port valve, and condensed through heat exchange with outdoor air. The condensed refrigerant is then moved to the expansion device.
In the expansion device, the refrigerant is expanded at a low temperature and a low pressure, and sent to the indoor heat exchanger, where the refrigerant absorbs the heat of the indoor air and is evaporated. This evaporated refrigerant is returned to the compressor.
As the indoor blowing fan rotates, the indoor air passes through the indoor heat exchanger and is cooled therein. Then, the cooled air is emitted back to the interior, cooling the air in the indoor space to a designated temperature.
The operation of the heating and cooling system in an air heating mode is now described.
The compressed refrigerant at a high temperature and a high pressure in the compressor is led to the indoor heat exchanger via the four-port valve, and condensed by releasing heat energy into the indoor air. The condensed refrigerant is then moved to the expansion device.
The indoor air is heated up as it passes through the indoor heat exchanger, being guided by the indoor blowing fan. Later, the hot air is emitted back to the interior, heating up the air in the indoor space to a designated temperature.
In the expansion device, the refrigerant is expanded at a low temperature and a low pressure, and sent to the outdoor heat exchanger, where the refrigerant absorbs the heat of the outdoor air, and it is returned to the compressor.
Performing the above procedures in a cycle, a user can adjust the temperature of the indoor space, heating or cooling as desired.
However, the general heating and cooling system has the following defects.
First of all, since the heating and cooling processes by the general heating and cooling system are performed by repeatedly circulating the indoor air, with doors and windows shut down. Thus after a certain amount of time, the air of the interior gets dry and stuffy, so the user usually opens the window to ventilate indoor spaces.
In so doing, that is, ventilating indoor spaces by emitting the indoor air to the outside, a lot of heat is lost and as the user turns on the system again after the ventilation, power consumption is sharply increased.
To solve the foregoing problems and disadvantages, a heating and cooling system that is capable of heating, cooling and ventilating the air within indoor spaces, and reducing heat loss during the ventilation, is needed.